November 26, 2024, 04:37:41 AM
Forum Rules: Read This Before Posting


Topic: How much heat will be absorbed / released if a compound isothermally....cont.  (Read 1830 times)

0 Members and 1 Guest are viewing this topic.

Offline birdnerd007

  • New Member
  • **
  • Posts: 4
  • Mole Snacks: +0/-0
Edit: I figure it out.
How much heat will be absorbed/released if a compound isothermally transforms from one phase to another? i.e. cristobalite to quartz.

I think the answer is non-zero but, I'm really not sure. Is this something that I should have on a chart? I have the specific heat capacities for both.
« Last Edit: October 18, 2019, 05:19:17 PM by birdnerd007 »

Offline Enthalpy

  • Chemist
  • Sr. Member
  • *
  • Posts: 4036
  • Mole Snacks: +304/-59
Hi birdnerd007, the heat capacities won't tell that. You need the heat of formation for both compounds, where "quartz" isn't as accurate as the considered allotrope.

The heat of transformation is small, so you need accurate heats of formation. I wouldn't be surprised if the heat of transformation was measured directly and is more accurate than both heats of formation.

Sponsored Links